Daryl Jacob's replacement aboard Kauto Stone in the William Hill King George VI Chase at Kempton on Boxing Day has still to be decided.

Jacob won the JNWine.com Champion Chase at Down Royal on Kauto Star's half-brother, but a suspension picked up at Wincanton for mistaking the winning line has ruled him out of the potentially lucrative Festive period.

Tony McCoy's name has been linked with the mount with trainer Paul Nicholls admitting last week that he had tentatively approached the rider's agent, but Charlie Liverton, racing manager to owner Robin Geffen, stated that as yet discussions remain ongoing.

With the recently-retired Kauto Star having dominated the race recently, Liverton hopes Kauto Stone can continue family tradition.

"Nothing has been finalised yet," said Liverton. "Mr (Robin) Geffen (owner) and Paul Nicholls still need to sit down and come to a decision.

"He's very much on target for the race, though, and has been doing everything nicely since Down Royal, touch wood.

"Being there will just be a dream, but at this stage that's all it is as this game has a habit of bringing you back down to earth, as we found out on Saturday with Cristal Bonus when he had to be put down.

"He was just beginning to realise his potential and it's such a shame."